解剖学报

解剖学报 ›› 2015, Vol. 46 ›› Issue (5): 649-654.doi: 10.16098/j.issn.0529-1356.2015.05.013

• 组织学胚胎学发育生物学 • 上一篇    下一篇

骨形态发生蛋白-2在小鼠胚胎心流出道发育中的作用

屈旭宽 洪肖杨 景雅 杨艳萍 许智慧 崔慧林 乔从进 李海荣*   

  1. 山西医科大学组织学胚胎学教研室，太原 030001
  • 收稿日期:2015-02-09 修回日期:2015-03-19 出版日期:2015-10-06 发布日期:2015-10-06
  • 通讯作者: 李海荣 E-mail:lihairong20030829@163.com
  • 基金资助:

    国家自然科学基金资助项目;山西省自然科学基金资助项目;山西省回国留学人员科研资助项目;山西省优势学科;山西医科大学博士启动基金

Contributions of bone morphogenetic protein -2 to a cardiac outflow tract in the development of the mouse embryo

QU Xu-kuan HONG Xiao-yang JING Ya YANG Yan-ping XU Zhi-hui CUI Hui-lin QIAO Cong-jin LI Hai-rong*   

  1. Department of Histology and Embryology of Shanxi Medical University, Taiyuan 030001, China
  • Received:2015-02-09 Revised:2015-03-19 Online:2015-10-06 Published:2015-10-06
  • Contact: LI Hai-rong E-mail:lihairong20030829@163.com

摘要：

目的 探讨骨形态发生蛋白-2(BMP-2)在小鼠胚胎心流出道发育过程中的作用。 方法 对胚龄9d(E9) ～E15（各胚龄取3～7只）小鼠心连续石蜡切片，用抗α-横纹肌肌动蛋白(α-SCA)抗体、抗胰岛素增强子结合蛋白(ISL-1)抗体、抗增殖细胞核抗原(PCNA)抗体、抗BMP-2抗体进行免疫组织化学染色。结果 E9，流出道心胶质内无细胞，心肌增殖活性低，BMP-2弱表达于流出道心肌、心内膜及心包腔背侧壁。E9～11，流出道增长，心包腔背侧壁ISL-1阳性细胞至流出道远端分化为心肌细胞后增殖逐渐减弱。E10～11，流出道嵴内间充质细胞逐渐增加，可见BMP-2、PCNA阳性细胞；流出道BMP-2表达逐渐增强达高峰，向两端延伸逐渐减弱，动脉端可及心包反折处。E12，流出道缩短，BMP-2表达减弱。E13～15，流出道隔逐渐肌化，BMP-2在心脏近大血管部心肌呈较弱表达。E10～13，流出道远段心肌呈低增殖活性，近段及右心室心肌增殖成小梁致右心室形成及扩大。结论 BMP-2诱导第二生心区(SHF)细胞分化为心肌细胞添加至心动脉端，参与心流出道嵴的发育。BMP-2抑制流出道心肌增殖，流出道近段BMP2表达减弱重启了心肌细胞增殖，致右心室形成及流出道缩短。低水平的BMP2可能诱导流出道隔间充质细胞向心肌分化。

关键词: 胚胎, 心流出道, 骨形态发生蛋白-2, 增殖细胞核抗原, 胰岛素增强子结合蛋白, 免疫组织化学, 小鼠

Abstract:

Objective To explore the contribution of bone morphogenetic protein-2 (BMP-2) in the development of the cardiac outflow tract(OFT) of the mouse embryo.
Methods Serial paraffin sections of mouse embryonic hearts from embryonic day 9(E9) to E15 were stained with antibodies against α-sarcomeric actin(α-SCA), islet-1(ISL-1), proliferating cell nuclear antigen(PCNA) or BMP-2 by the immunohistochemical method. Three to seven mice were examined for each stage. Results At E9, no cell was observed in the cardiac jelly of OFT. Scarce PCNA expressing cells were found in OFT myocardium. Weak BMP-2 expressed in the OFT myocardium, endocardium and dorsal pericardium. During E9-11, with the addition of cardiomyocytes derived from the second heart field to the arterial pole, the OFT lengthened. The proliferation rate of these newly added cells dropped gradually during recruitment into the OFT. During E10-11, mesenchymal cells gradually filled the OFT ridges, some of them expressing BMP-2, PCNA. BMP-2 expression in myocardium of OFT was up-regulated to the peak at the stages and tapered off toward the poles, reaching up to the reflection of pericardium at the arterial pole. At E12, the OFT shortened and its BMP-2 expression level was down-regulated. During E13-15, the mesenchymal outlet septum were gradually myocardialized and weak BMP-2 expression was restricted to the OFT myocardium adjacent to the great vessels. During E10~13, myocardium of the distal OFT showed low proliferation activity while myocardium of the proximal OFT and right ventricle proliferated into trabeculae and resulted in the development of right ventricle. Conclusion BMP-2 induceds the precursors from the second heart field to differentiate into cardiomyocytes and add to the arterial pole of the heart. BMP-2 is participated in the development of OFT ridges. BMP-2 inhibites cardiomyocytes of OFT proliferating and its down-regulation in the proximal portion reinitiated cardiomyocytes proliferating, which leads to the development of right ventricle and shortening of the OFT. Low level of BMP-2 might induce mesenchymal cells in OFT septum to differentiate into cardiomyocytes.

Key words: Embryo, Cardiac outflow tract, Bone morphogenetic protein-2, Proliferating cell nuclear antigen, Islet-1, Immunohistochemistry, Mouse